gnopls, the Gno language server

gnopls is a modified fork of https://github.com/golang/tools/tree/master/gopls

⚠️ gnopls is in an experimental phase; use with caution.

It provides a wide variety of IDE features to any [LSP]-compatible editor.

Editor Setup

gnopls is compatible with any editor that supports the Language Server Protocol (LSP). Below are setup instructions for popular editors.

Visual Studio Code

There is an unofficial Visual Studio Code extension for working with *.gno files that includes LSP support.

1. Install the extension from the VS Code Marketplace
2. The extension will automatically use gnopls if it's installed in your PATH

Vim/Neovim

Prerequisites

• Install gnopls: go install github.com/gnoverse/gnopls@latest
• Set GNOROOT environment variable to your gno repository path

Using vim-lsp

Install the vim-lsp plugin, then add to your .vimrc:

augroup gno_autocmd
    autocmd!
    autocmd BufNewFile,BufRead *.gno
        \ set filetype=gno |
        \ set syntax=go
augroup END

if (executable('gnopls'))
    au User lsp_setup call lsp#register_server({
        \ 'name': 'gnopls',
        \ 'cmd': ['gnopls'],
        \ 'allowlist': ['gno'],
        \ 'config': {},
        \ 'languageId': {server_info->'gno'},
    \ })
else
    echomsg 'gnopls binary not found: LSP disabled for Gno files'
endif

function! s:on_lsp_buffer_enabled() abort
    " Autocompletion
    setlocal omnifunc=lsp#complete
    " Format on save
    autocmd BufWritePre <buffer> LspDocumentFormat
    " Key mappings
    nmap <buffer> gd <plug>(lsp-definition)
    nmap <buffer> <leader>rr <Plug>(lsp-rename)
    nmap <buffer> <leader>ri <Plug>(lsp-implementation)
    nmap <buffer> <leader>rf <Plug>(lsp-references)
    nmap <buffer> <leader>i <Plug>(lsp-hover)
endfunction

augroup lsp_install
    au!
    autocmd User lsp_buffer_enabled call s:on_lsp_buffer_enabled()
augroup END

Using Neovim built-in LSP

For Neovim users, you can use the built-in LSP client. Add to your init.lua:

-- Register .gno files
vim.filetype.add({
  extension = {
    gno = 'gno',
  },
})

-- Set up gnopls
local lspconfig = require('lspconfig')
local configs = require('lspconfig.configs')

if not configs.gnopls then
  configs.gnopls = {
    default_config = {
      cmd = {'gnopls'},
      filetypes = {'gno'},
      root_dir = lspconfig.util.root_pattern('gnomod.toml', '.git'),
      settings = {},
    },
  }
end

lspconfig.gnopls.setup{}

Emacs

1. Install go-mode.el
2. Add to your Emacs configuration:

;; Define gno-mode based on go-mode
(define-derived-mode gno-mode go-mode "GNO"
  "Major mode for GNO files, an alias for go-mode."
  (setq-local tab-width 8))

(define-derived-mode gno-dot-mod-mode go-dot-mod-mode "GNO Mod"
  "Major mode for GNO mod files, an alias for go-dot-mod-mode.")

;; Register file associations
(add-to-list 'auto-mode-alist '("\\.gno\\'" . gno-mode))
(add-to-list 'auto-mode-alist '("gnomod\\.toml\\'" . gno-dot-mod-mode))

LSP Setup with lsp-mode

If using lsp-mode:

(with-eval-after-load 'lsp-mode
  (add-to-list 'lsp-language-id-configuration '(gno-mode . "gno"))
  
  (lsp-register-client
   (make-lsp-client
    :new-connection (lsp-stdio-connection "gnopls")
    :major-modes '(gno-mode)
    :language-id "gno"
    :server-id 'gnopls)))

(add-hook 'gno-mode-hook #'lsp-deferred)

Flycheck Integration

For linting with Flycheck:

(require 'flycheck)

(flycheck-define-checker gno-lint
  "A GNO syntax checker using the gno lint tool."
  :command ("gno" "lint" source-original)
  :error-patterns ((error line-start (file-name) ":" line ": " (message) " (code=" (id (one-or-more digit)) ")." line-end))
  :predicate (lambda ()
               (and (not (bound-and-true-p polymode-mode))
                    (flycheck-buffer-saved-p)))
  :modes gno-mode)

(add-to-list 'flycheck-checkers 'gno-lint)

Sublime Text

There is a community-developed Gno Language Server with installation instructions for Sublime Text.

Zed

A community-developed extension for Zed is available at julienrbrt/zed-gno.

Other Editors

If you use gnopls with an editor that is not on this list, please send us a PR to add instructions!

Installation

For the most part, you should not need to install or update gnopls. Your editor should handle that step for you.

If you do want to get the latest stable version of gnopls, run the following command:

go install github.com/gnoverse/gnopls@latest